thump under left foot

[gofast]

as the title says, i'm getting a thump under my left foot when coming to a stop, its almost like something hitting the tunnel.

i've tipped the sled over and checked everything and the bearing is tight plus not heating up. no codes flashing.

one thing i will mention is the clutch has an aftermarket spring, but ive riden the sled and didn't have the problem till this weekend.

another thing is when i unload the sled in reverese and put it back in fprwaed the belt seems to howl for 20ft or so like it's slipping.

anybody got any ideas on wheat this could be

thanks

 

[MrSled]

I have 13500 miles on my Apex and I get that too... I tore that sled apart and found nothing... I looked at the drivers and they are warn heavy on one side... I think the track is sticking to the extrovert driver.. it only happens at really slow/crawl speeds.

 

[gofast]

I have 13500 miles on my Apex and I get that too... I tore that sled apart and found nothing... I looked at the drivers and they are warn heavy on one side... I think the track is sticking to the extrovert driver.. it only happens at really slow/crawl speeds.

yep, same thing. almost at a walking pace.do you mean the drive sprockets that drive the track?

i'm going to put a bearing in it for piece of mind

 

[MrSled]

yep, same thing. almost at a walking pace.

i'm going to put a bearing in it for piece of mind

It cant hurt to at least rule that out.

 

[gytrapex]

Mine dose it to feel like it hit some thing

 

[gofast]

i'm thinking it might be a belt that has flat spotted, gonna start there first

 

[STAIN]

I have seen 2 Apexs with the same thing and it turned out to be the collar on the left side drive bearing was loose, not enough to see but when you went to tighten the collar locking screws they were loose.

 

[MrSled]

Mine still does it... cant find the gremlin

 

[tomanytoyz]

You said when coming to a stop you feel it.check to see if your black sliders are all there in your secondary and in good shape.all even wear.

 

[Timeline]

I just had the same feeling when coming to a crawl - stop. It ended up being my drive shaft bearing. I have 13.700 miles on my Apex and the bearings are replaced every year. I've been going the cheap route with the All Balls kit and have had luck up until this year. Last years bearing that had 3000 miles on it felt better then the one I just replaced with 500 miles on it. Luck of the draw I guess. I've used the cheap alternative because I figure I replace them every season. Not anymore.

What lead me to this was actually feeling the thump with my hand while in motion. Disclaimer,,,,, Please be careful. For trained professionals only!
While warmed up after a ride, I had it up on a track stand with the track turning slowly by itself at idle. While laying on the ground with my head at the bottom of the sled and my hand carefully placed on the bearing plate and speedo sensor I was able to feel an intermittent thump. With the shield popped off it didn't actually look that bad besides the water and grit. I don't know how I was able to feel it. When washed out it has some side play, but minimal with slight roughness. I'm guessing side binding from slight twist caused the thumping.

 

[MrSled]

I just had the same feeling when coming to a crawl - stop. It ended up being my drive shaft bearing. I have 13.700 miles on my Apex and the bearings are replaced every year. I've been going the cheap route with the All Balls kit and have had luck up until this year. Last years bearing that had 3000 miles on it felt better then the one I just replaced with 500 miles on it. Luck of the draw I guess. I've used the cheap alternative because I figure I replace them every season. Not anymore.

What lead me to this was actually feeling the thump with my hand while in motion. Disclaimer,,,,, Please be careful. For trained professionals only!
While warmed up after a ride, I had it up on a track stand with the track turning slowly by itself at idle. While laying on the ground with my head at the bottom of the sled and my hand carefully placed on the bearing plate and speedo sensor I was able to feel an intermittent thump. With the shield popped off it didn't actually look that bad besides the water and grit. I don't know how I was able to feel it. When washed out it has some side play, but minimal with slight roughness. I'm guessing side binding from slight twist caused the thumping.

Still have it after the bearings have been replaced... thats not my gremlin fix.

 

[Timeline]

Still have it after the bearings have been replaced... thats not my gremlin fix.

Well at least we'll have the piece of mind of new bearings. You likely nailed it with the worn drive sprockets thought. I'm about due for a second set and drive shaft again too.

Ride on and good luck.

 

[MrSled]

Well at least we'll have the piece of mind of new bearings. You likely nailed it with the worn drive sprockets thought. I'm about due for a second set and drive shaft again too.

Ride on and good luck.

I am too... 13500 miles on them.. drivers are undercut pretty good too.

 

[gofast]

well i think i found my problem, had the belt come apart on me today.

changed it out and problem was gone. or for the 5k's i rode anyways

 

[machzrobbie]

Are these both mono shock suspensions??